Incidence of liver cancer and decompensated cirrhosis amongst hepatitis B and C notifications in Tasmania- a data linkage study

Liver cancer is a leading cause of cancer-related death globally, with both incidence and mortality rates rising sharply in Australia over the past three decades. Chronic hepatitis B and C are major contributors to liver cancer, and its common precursor, decompensated cirrhosis. This study assessed the incidence of liver cancer and decompensated cirrhosis among individuals with hepatitis B and C in Tasmania. A retrospective population-based study was conducted using linked datasets. The cohort included all individuals with a notification for hepatitis B and/or C in Tasmania from 1995 to 2022. Cases were linked to the Tasmanian Cancer Register and admitted patient data from Tasmanian public hospitals. Incidence rates per 1,000 person-years were calculated for liver cancer and decompensated cirrhosis. Between 1995 and 2022, 1,280 hepatitis B (55.5% male) and 6,658 hepatitis C (64.3% male) notifications were recorded in Tasmania. A total of 145 liver cancer registrations and 270 decompensated cirrhosis-related admissions were observed. Among individuals with hepatitis B, the incidence rates were 5.39 per 1,000 person-years for liver cancer and 3.00 per 1,000 person-years for decompensated cirrhosis. Among those with hepatitis C, corresponding rates were 2.33 and 5.02 per 1,000 person-years. While the number of liver-related outcomes was relatively low and did not support more detailed analyses, a trend towards higher incidence rates was observed over the study period. These findings highlight the burden of liver-related complications among individuals with hepatitis B and C in Tasmania. Liver cancer was more common among those with hepatitis B, while decompensated cirrhosis was more frequent among those with hepatitis C. Observed trends should be interpreted cautiously, as they may reflect changes in population characteristics, surveillance, and healthcare engagement. Strengthening testing, treatment uptake, and long-term monitoring is essential to reduce the burden of advanced liver disease in this regional setting.